Last week at the Society of Automotive Engineers World Congress in Detroit, we spoke with Dr. Pete Savagian of General Motors about what the Chevrolet Volt's fuel economy sticker would look like. Last summer, former GM CEO Fritz Henderson made a big splash when he announced that the Volt was getting approximately 230 miles per gallon combined. However, that number was based on a draft proposal by the EPA for a testing methodology for plug-in vehicles.

Last week at the Society of Automotive Engineers World Congress in Detroit, we spoke with Dr. Pete Savagian of General Motors about what the Chevrolet Volt's fuel economy sticker would look like. Last summer former GM CEO Fritz Henderson made a big splash when he announced that the Volt was getting approximately 230 miles-per-gallon combined. However, that number was based on a draft proposal by the EPA for a testing methodology for plug-in vehicles.

Eight months ago, General Motors made a huge deal about how the Chevrolet Volt will get 230 miles per gallon. Of course, the company admitted that this isn't what drivers will actually experience when they use the car, just that the Volt is "expected to achieve city fuel economy of at least 230 miles per gallon, based on development testing using a draft EPA federal fuel economy methodology for labeling for plug-in electric vehicles."

So, plenty of time has passed since General Motors first made the announcement that its Chevy Volt extended-range electric vehicle would score 230 miles per gallon on the yet-to-be-completed EPA testing procedure for such vehicles. Still, lots of questions remain, such as How many miles per gallon with the Volt achieve after it has traveled the 40 or so miles necessary to deplete its battery pack?

So, plenty of time has passed since General Motors first made the announcement that its Chevy Volt extended-range electric vehicle would score 230 miles per gallon on the yet-to-be-completed EPA testing procedure for such vehicles. Still, plenty of questions remain, such as How many miles per gallon with the Volt achieve after it has traveled the 40 or so miles necessary to deplete its battery pack?

EPA mileage estimates can be such fuzzy things when you're dealing with hybrid powertrains. We've seen plenty of contention already about real-world results versus EPA numbers for current hybrids, and Chevrolet's upcoming Volt has GM butting heads with the Feds over how the series hybrid eFlex powertrain should be rated. Because the Volt can cover about 40 miles before it needs to fire its range-extending internal combustion engine, it can breeze through the EPA's test cycle with the engine off